title: Label-free electrochemical detection of short sequences related to the hepatitis B virus using 4,4'-diaminoazobenzene based on multiwalled carbon nanotube-modified GCE.
abstract: A novel label-free electrochemical DNA biosensor based on 4,4'-diaminoazobenzene (4,4'-DAAB) and multiwalled carbon nanotube (MWNT)-modified glassy carbon electrode (GCE) for short DNA sequences related to the hepatitis B virus (HBV) hybridization detection was presented. Differential pulse voltammetry (DPV) was used to investigate hybridization event. The decrease in the peak current of 4,4'-DAAB was observed on hybridization of probe with the target. This electrochemical approach was sequence specific as indicated by the control experiments, in which no peak current change was observed when a noncomplementary DNA sequence was used. Numerous factors affecting the target hybridization were optimized to maximize the sensitivity. Under optimal conditions, this sensor showed a good calibration range between 7.94 x 10(-8) M and 1.58 x 10(-6) M, with HBV DNA sequence detection limit of 1.1 x 10(-8) M.
authors.affiliation: College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao, People's Republic of China.
authors.forename: Xue-Mei
authors.initials: XM
authors.lastname: Li
authors.forename: Zhi-Ming
authors.initials: ZM
authors.lastname: Zhan
authors.forename: Heng-Qiang
authors.initials: HQ
authors.lastname: Ju
authors.forename: Shu-Sheng
authors.initials: SS
authors.lastname: Zhang
mesh_terms: D001483:Base Sequence; D015374:Biosensing Techniques / Q000379:methods*; D004279:DNA, Viral / Q000032:analysis*; D004566:Electrodes; D006515:Hepatitis B virus / Q000235:genetics / Q000302:isolation & purification*; D036103:Nanotechnology; D037742:Nanotubes, Carbon / Q000737:chemistry*; D009693:Nucleic Acid Hybridization / Q000379:methods*; D011199:Potentiometry; D012680:Sensitivity and Specificity; D004124:p-Dimethylaminoazobenzene / Q000737:chemistry*
chemical_list: D004279:DNA, Viral; D037742:Nanotubes, Carbon; D004124:p-Dimethylaminoazobenzene